The present invention relates to a method for supplying an internal combustion engine with liquefied petroleum gas (LPG) as fuel, and to a fuel supply system for an internal combustion engine which supplies the LPG to the engine.
A fuel supply system for blowing in LPG is already known, in which a metering of the vaporized LPG is effected in accordance with the air throughput in the intake manifold by means of a pressure measurement in a venturi. The pressure in the venturi varies with the square of the flow velocity, so that a desired metering of a quantity of LPG which is at a linear ratio with the aspirated air quantity cannot be made. Also, only a rough adaptation of the LPG-air mixture to the various operating states of the internal combustion engine can be made with the known apparatus, resulting in an increased consumption of LPG, reduced output and unfavorable exhaust gases. In metering the vaporized LPG, the danger also exists that oily components dissolved in the liquid LPG may be deposited as oily residues on the metering valve after the LPG has evaporated and cause errors in metering.